The point I want to make is regarding unique, first of their kind files, that sell a lot, that then go on to be copied (in most cases improved) by other authors.

OK so, original one-of-a-kind files sell a lot. Copycat’s files are improved with many more features. They sell too.

Erm, I’m sorry but isn’t this how almost everything works? Phones, movies, books, art, music, you name it. Follow the example of Apple. Take a phone and beat the crap out of competition that basically invented a lot of the “concepts” that go into a phone.

If there is a copyright infringement, then it is a different matter. Everything is an improvisation of something.